The subject matter disclosed herein relates to reciprocating engines and, more specifically, to exhaust valves for reciprocating engines.
This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present disclosure, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
A reciprocating engine (e.g., an internal combustion engine such as a diesel engine) combusts fuel with an oxidant (e.g., air) in a combustion chamber to generate hot combustion gases, which in turn drive a piston (e.g., reciprocating piston) within a cylinder. In particular, the hot combustion gases expand and exert a pressure against the piston that linearly moves the position of the piston from a top portion to a bottom portion of the cylinder during an expansion stroke. The piston converts the pressure exerted by the hot combustion gases (and the piston's linear motion) into a rotating motion (e.g., via a connecting rod and a crankshaft coupled to the piston) that drives one or more loads, for example, an electrical generator. A cylinder head is generally at a top of the cylinder, above the piston and other components of the cylinder. The cylinder head may include a poppet valve (e.g., an intake and/or exhaust valve). Similar to the piston, the poppet valve reciprocates to allow a flow of fluids (e.g., fuel, air, exhaust gases) in and out of the combustion chamber. For example, during engine operation, the poppet valve may open and close a fluid passage within the cylinder head to control an influx of fuel (and air) into the combustion chamber, and an efflux of exhaust gases out of the combustion chamber.
The poppet valve, in particular the exhaust valve, is exposed to the operational conditions of the combustion chamber such as elevated temperatures and combustion byproducts (e.g., exhaust gases, carbon particulates, etc.). Therefore, the poppet valve may need to be cooled to mitigate thermal stress and overheating.